System and method for efficiently synchronizing cache and persistent data in an object oriented transaction processing system

Abstract

A system and method for effectively synchronizing data in an object oriented distributed transaction processing system employing a multilevel data store. Each object that maintains first-level volatile data registers as a synchronization object if unsynchronized changes to that data exist. A register object at each node tracks synchronized objects registered for that node. Each registered synchronization object, in turn, registers with its superior node when registered synchronization objects are present. A hierarchy of registered synchronization objects and synchronization objects is thereby created. The transaction termination process transmits a pre-prepare message to the registered synchronization hierarchy providing each synchronization object an opportunity to flush its data to the second-level persistent data store. The hierarchical structure of registered objects ensures that the minimum number of messages are transmitted over the network.

We claim: 
     
       1. A system for synchronizing volatile transaction processing object data with permanent data in a computer system having a processing node with processor means, memory and permanent storage means, the system comprising: termination means for controlling transaction processing transaction termination,   means for registering with said termination means an object having data requiring synchronization before transaction termination, wherein said object does not otherwise participate in termination processing;   means for notifying only registered objects before transaction completion processing, said means for notifying being responsive to said transaction means and said means for registering   a plurality of additional processing nodes each having processor means and memory, and   wherein the means for registering includes means for registering at most one object for each additional processing node having an object requiring synchronization; and   wherein the means for notifying includes: means for testing whether an additional processing node has any objects requiring synchronization; and   means for sending one and only one notification to each processing node that contains objects requiring synchronization.